All right, Martha, thank you. More from our aviation cons consultant Steve ganyard. This is a crash site, crime scene in a war zone. It sure is, George. I want to pick up on one thing Martha just said there and the idea that back on June 30th, nato intelligence was briefing that the rebels were seen being trained by the Russians on the sophisticated tactical mobile S.A.M.S, almost all can reach up to 45,000, 50,000 feet above where an airliner could fly so why they're not saying that's not a safe altitude is a question that needs to be asked because I think there's a real disconnect. Especially since the plane had gone down earlier in the week. Conflicting reports on what happened to the black boxes. The rebels say they recovered some and talked about having eight different black boxes which is kind of unusual, isn't it? Yes, George, there are just two. I'd like to move us away from the black boxes a little bit. We're getting U.S. Officials this morning are pretty much confirming that a missile brought this aircraft down and so the black boxes are not going to tell us too much. The shoot-down came down as a real shock. It was on autopilot at 33,000 feet and, bang, the missile hit and that was the end. It's not like the black boxes will be a clue the way they would be in a mishap where there was pilot error or a mechanical failure. The real key, get to the site and to look at the forensic evidence on the skin of the aircraft. The U.S. Military has the ability to look at the forensic evidence of residue, explosive residue and the warhead and be able to determine from the metal and the residue what kind of missile might have hit that aircraft so I think it's much more important to get to the site, to find the aircraft, rather than search so hard for the black boxes. And why it's so important to have an independent investigation because that could presumably tell you whether it was a system more likely to be inside Ukrainian territory or over in Russian territory. Exactly. It's just like a crime scene vision. You don't want anybody to touch it. You want it pristine. You don't want anything moved. You have to preserve the evidence in the way that it appears when the aircraft came down or it could be contaminated and the improper conclusions could be drawn. Okay, Steve ganyard. Thanks very much.

This transcript has been automatically generated and may not be 100% accurate.

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